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std::basic_iostream(3)	      C++ Standard Libary	std::basic_iostream(3)

NAME
       std::basic_iostream - std::basic_iostream

Synopsis
	  Defined in header <istream>
	  template<

	  class	CharT,
	  class	Traits = std::char_traits<CharT>

	  > class basic_iostream;

	  The  class  template	basic_iostream provides	support	for high level
       input/output
	  operations on	streams. The supported operations  include  sequential
       reading or
	  writing  and	formatting. This functionality is implemented over the
       interface
	  provided by the basic_streambuf class. It is	accessed  through  ba-
       sic_ios class.

	  std-basic iostream-inheritance.svg

					  Inheritance diagram

	  Two specializations for common character types are defined:

	  Defined in header <istream>
	  Type	    Definition
	  iostream  basic_iostream<char>
	  wiostream basic_iostream<wchar_t>

Member types
	  Member type Definition
	  char_type   CharT
	  traits_type  Traits;	the program is ill-formed if Traits::char_type
       is not CharT.
	  int_type    Traits::int_type
	  pos_type    Traits::pos_type
	  off_type    Traits::off_type

Member functions
	  constructor	constructs the object
			(public	member function)
	  destructor	destructs the object
	  [virtual]	(virtual public	member function)

Protected member functions
	  operator= move-assigns another basic_iostream
	  (C++11)   (protected member function)
	  swap	    exchanges the state	with another basic_iostream
	  (C++11)   (public member function)

       Inherited from std::basic_istream

Member functions
Formatted input
	  operator>> extracts formatted	data
		     (public	  member      function	     of	      std::ba-
       sic_istream<CharT,Traits>)

Unformatted input
	  get	     extracts characters
		     (public	   member	function      of      std::ba-
       sic_istream<CharT,Traits>)
	  peek	     reads the next character without extracting it
		     (public	  member      function	     of	      std::ba-
       sic_istream<CharT,Traits>)
	  unget	     unextracts	a character
		     (public	   member	function      of      std::ba-
       sic_istream<CharT,Traits>)
	  putback    puts character into input stream
		     (public	  member      function	     of	      std::ba-
       sic_istream<CharT,Traits>)
	  getline    extracts characters until the given character is found
		     (public	   member	function      of      std::ba-
       sic_istream<CharT,Traits>)
	  ignore     extracts and discards characters until the	given  charac-
       ter is found
		     (public	   member	function      of      std::ba-
       sic_istream<CharT,Traits>)
	  read	     extracts blocks of	characters
		     (public	  member      function	     of	      std::ba-
       sic_istream<CharT,Traits>)
	  readsome   extracts already available	blocks of characters
		     (public	   member	function      of      std::ba-
       sic_istream<CharT,Traits>)
		     returns number of characters extracted by last  unformat-
       ted input
	  gcount     operation
		     (public	   member	function      of      std::ba-
       sic_istream<CharT,Traits>)

Positioning
	  tellg	     returns the input position	indicator
		     (public	  member      function	     of	      std::ba-
       sic_istream<CharT,Traits>)
	  seekg	     sets the input position indicator
		     (public	   member	function      of      std::ba-
       sic_istream<CharT,Traits>)

Miscellaneous
	  sync	     synchronizes with the underlying storage device
		     (public	  member      function	     of	      std::ba-
       sic_istream<CharT,Traits>)

Member classes
	  sentry  implements basic logic for preparation of the	stream for in-
       put operations
		 (public member	class of std::basic_istream<CharT,Traits>)

       Inherited from std::basic_ostream

Member functions
Formatted output
	  operator<< inserts formatted data
		     (public	 member	    function	 of	std::basic_os-
       tream<CharT,Traits>)

Unformatted output
	  put	     inserts a character
		     (public	 member	    function	 of	std::basic_os-
       tream<CharT,Traits>)
	  write	     inserts blocks of characters
		     (public	 member	    function	 of	std::basic_os-
       tream<CharT,Traits>)

Positioning
	  tellp	     returns the output	position indicator
		     (public	 member	    function	 of	std::basic_os-
       tream<CharT,Traits>)
	  seekp	     sets the output position indicator
		     (public	 member	    function	 of	std::basic_os-
       tream<CharT,Traits>)

Miscellaneous
	  flush	     synchronizes with the underlying storage device
		     (public	 member	    function	 of	std::basic_os-
       tream<CharT,Traits>)

Member classes
	  sentry implements basic logic	for preparation	of the stream for out-
       put operations
		 (public member	class of std::basic_ostream<CharT,Traits>)

       Inherited from std::basic_ios

Member types
	  Member type Definition
	  char_type   CharT
	  traits_type Traits
	  int_type    Traits::int_type
	  pos_type    Traits::pos_type
	  off_type    Traits::off_type

Member functions
State functions
	  good		 checks	if no error has	occurred i.e.  I/O  operations
       are available
			 (public      member	  function     of     std::ba-
       sic_ios<CharT,Traits>)
	  eof		 checks	if end-of-file has been	reached
			 (public     member	function      of      std::ba-
       sic_ios<CharT,Traits>)
	  fail		 checks	if an error has	occurred
			 (public      member	  function     of     std::ba-
       sic_ios<CharT,Traits>)
	  bad		 checks	if a non-recoverable error has occurred
			 (public     member	function      of      std::ba-
       sic_ios<CharT,Traits>)
	  operator!	 checks	if an error has	occurred (synonym of fail())
			 (public      member	  function     of     std::ba-
       sic_ios<CharT,Traits>)
	  operator void*
	  operator bool	 checks	if no error has	occurred (synonym of !fail())
	  (until    C++11)     (public	  member    function	of    std::ba-
       sic_ios<CharT,Traits>)
	  (since C++11)
	  rdstate	 returns state flags
			 (public      member	  function     of     std::ba-
       sic_ios<CharT,Traits>)
	  setstate	 sets state flags
			 (public     member	function      of      std::ba-
       sic_ios<CharT,Traits>)
	  clear		 modifies state	flags
			 (public      member	  function     of     std::ba-
       sic_ios<CharT,Traits>)

Formatting
	  copyfmt	 copies	formatting information
			 (public     member	function      of      std::ba-
       sic_ios<CharT,Traits>)
	  fill		 manages the fill character
			 (public      member	  function     of     std::ba-
       sic_ios<CharT,Traits>)

Miscellaneous
	  exceptions	 manages exception mask
			 (public     member	function      of      std::ba-
       sic_ios<CharT,Traits>)
	  imbue		 sets the locale
			 (public      member	  function     of     std::ba-
       sic_ios<CharT,Traits>)
	  rdbuf		 manages associated stream buffer
			 (public     member	function      of      std::ba-
       sic_ios<CharT,Traits>)
	  tie		 manages tied stream
			 (public      member	  function     of     std::ba-
       sic_ios<CharT,Traits>)
	  narrow	 narrows characters
			 (public     member	function      of      std::ba-
       sic_ios<CharT,Traits>)
	  widen		 widens	characters
			 (public      member	  function     of     std::ba-
       sic_ios<CharT,Traits>)

       Inherited from std::ios_base

Member functions
Formatting
	  flags		    manages format flags
			    (public member function of std::ios_base)
	  setf		    sets specific format flag
			    (public member function of std::ios_base)
	  unsetf	    clears specific format flag
			    (public member function of std::ios_base)
	  precision	    manages decimal precision of floating point	opera-
       tions
			    (public member function of std::ios_base)
	  width		    manages field width
			    (public member function of std::ios_base)

Locales
	  imbue		    sets locale
			    (public member function of std::ios_base)
	  getloc	    returns current locale
			    (public member function of std::ios_base)

Internal extensible array
	  xalloc	    returns a program-wide unique integer that is safe
       to use as index
	  [static]	    to pword() and iword()
			    (public static member function of std::ios_base)
			    resizes the	private	storage	if necessary  and  ac-
       cess to the long
	  iword		    element at the given index
			    (public member function of std::ios_base)
			    resizes  the  private storage if necessary and ac-
       cess to the void*
	  pword		    element at the given index
			    (public member function of std::ios_base)

Miscellaneous
	  register_callback registers event callback function
			    (public member function of std::ios_base)
	  sync_with_stdio   sets whether C++ and C I/O libraries are  interop-
       erable
	  [static]	    (public static member function of std::ios_base)

Member classes
	  failure	    stream exception
			    (public member class of std::ios_base)
	  Init		    initializes	standard stream	objects
			    (public member class of std::ios_base)

Member types and constants
	  Type		 Explanation
			 stream	open mode type

			 The following constants are also defined:

			 Constant Explanation
			 app	  seek to the end of stream before each	write
	  openmode	 binary	  open in binary mode
			 in	  open for reading
			 out	  open for writing
			 trunc	   discard  the	 contents  of  the stream when
       opening
			 ate	  seek to the end of stream immediately	 after
       open

			 (typedef)
			 formatting flags type

			 The following constants are also defined:

			 Constant    Explanation
			 dec	      use  decimal  base  for integer I/O: see
       std::dec
			 oct	     use  octal	 base  for  integer  I/O:  see
       std::oct
			 hex	     use hexadecimal base for integer I/O: see
       std::hex
			 basefield    dec|oct|hex.  Useful  for	masking	opera-
       tions
			 left	     left adjustment (adds fill	characters  to
       the right): see
				     std::left
			 right	     right adjustment (adds fill characters to
       the left): see
				     std::right
			 internal    internal adjustment (adds fill characters
       to the internal
				     designated	point):	see std::internal
			 adjustfield  left|right|internal.  Useful for masking
       operations
				     generate floating point types using  sci-
       entific notation,
			 scientific   or  hex notation if combined with	fixed:
       see
				     std::scientific
	  fmtflags	 fixed	     generate floating point types using fixed
       notation, or
				     hex notation if combined with scientific:
       see std::fixed
			 floatfield  scientific|fixed. Useful for masking  op-
       erations
			 boolalpha    insert and extract bool type in alphanu-
       meric format: see
				     std::boolalpha
				     generate a	prefix indicating the  numeric
       base for	integer
			 showbase    output, require the currency indicator in
       monetary	I/O:
				     see std::showbase
			 showpoint   generate a	decimal-point character	uncon-
       ditionally for
				     floating-point    number	 output:   see
       std::showpoint
			 showpos     generate a	+ character  for  non-negative
       numeric output:
				     see std::showpos
			 skipws	      skip  leading  whitespace	before certain
       input operations:
				     see std::skipws
			 unitbuf     flush the output after each output	opera-
       tion: see
				     std::unitbuf
				     replace certain  lowercase	 letters  with
       their uppercase
			 uppercase   equivalents in certain output operations:
       see
				     std::uppercase

			 (typedef)
			 state of the stream type

			 The following constants are also defined:

			 Constant Explanation
	  iostate	 goodbit  no error
			 badbit	  irrecoverable	stream error
			 failbit  input/output operation failed	(formatting or
       extraction
				  error)
			 eofbit	   associated  input sequence has reached end-
       of-file

			 (typedef)
			 seeking direction type

			 The following constants are also defined:

	  seekdir	 Constant Explanation
			 beg	  the beginning	of a stream
			 end	  the ending of	a stream
			 cur	  the current position of stream position  in-
       dicator

			 (typedef)
	  event		 specifies event type
			 (enum)
	  event_callback callback function type
			 (typedef)

See also
	  Input/output manipulators

http://cppreference.com		  2022.07.31		std::basic_iostream(3)

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